視訊濃縮(video synopsis)或稱視頻摘要(video summarization)技術主要的用途為去除長時間視訊中空間域(spatial domain)以及時間域(temporal domain)的冗餘資訊並提供濃縮摘要視訊，藉由改變原始視訊中物件的時間空間關聯性來達成此一目的。現今存在的視訊濃縮演算法皆有一前提，假設所有物件串列(同一物件不同時間的集合)皆是獨立的並且可以從原始影片中完美的取出，可是此一前提在現實生活中是不可發生的，因為目前尚無物件追蹤演算法保證能克服強烈的光影變化或是物件重疊所導致的追蹤失敗，另外，現今的濃縮視訊演算法所使用到的能量最小化演算法有著高計算複雜度的缺點，進而影響到此技術的實用性。
有鑑於此，本論文針對以上缺點提出了高效率無失真視訊濃縮技術，優點如下 (1) 提出了動態邊緣調整演算法，克服多層式高速背景濾除技術中所會造成的物件邊緣破損或破洞等問題。(2) 視訊濃縮整體演算法的處理速度超過即時視訊處理要求的數倍，因此演算法可以達到同時多路並行處理。(3) 對於視訊濃縮的應用上克服了前置技術(背景濾除、物件追蹤)所造成的問題，在不以速度為代價的前提下取得自然流暢(non-artifacts)的濃縮視訊。(4) 提出了基於相關性分群與機率權重函數的視訊濃縮演算法，克服前人採用能量最佳化所造成的效率低落問題。
最後實驗結果也顯示出本論文所提出的高效率視訊濃縮演算法除了可以達到即時多路的處理外，其產生的濃縮視訊可以克服物件追蹤失敗在濃縮視訊中所產生的閃爍現象(blink effect)與鬼影現象(ghost effect)。

Video synopsis is utilized to provide a condensed video without spatial and temporal redundancies, while maintaining all the activities in the original video. Existing video synopsis methods presume that the object tubes (three dimension space time volume) are perfectly retrieved from the original video, yet it is not the case in practical applications due to the object detection/tracking failure or object collision. Another problem is the energy minimization based method often suffers from heavily computational cost, which thus prolongs the processing time. In this thesis, a new video synopsis scheme is proposed to solve the above issues.
The main contributions of this study are as follows: 1) A highly efficient background subtraction scheme with dynamic edge thresholding is proposed to provide an artifact-free video synopsis result, and preserve most of the non-specific objects; (2) the processing speed of the overall video synopsis is even faster than real-time requirement to enable the multi-channel scenario; (3) overcome the problems induced by the preprocessing such as background subtraction and object tracking, and create fluent synopsis video without decreasing processing speed, and (4) overcome the energy minimization problem in former works with the object correlation clustering and properity weighting function. As documented in the experimental results, the proposed scheme provides promising performance, and can be a very competitive candidate in the practical video synopsis application.

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